1. Field
The present invention relates generally to optical fibers, and more specifically to bend tolerant optical fibers that contain randomly distributed voids therein, and methods of polishing such fibers.
2. Technical Background
Optical fibers formed of glass materials have been in commercial use for more than two decades. Although such optical fibers have represented a quantum leap forward in the field of telecommunications, work on alternative optical fiber designs continues. One application space for fibers which has heretofore not been successfully exploited by optical fiber is fiber to the home. However, fibers which are to be employed in buildings and homes face many challenges. A fast and low skilled installation process is vital to keep costs down, which in turn dictates the use of an optical fiber cable that handles and installs as easily as copper—and yet has no adverse affects on the optical power budget. To ensure seamless interconnection with the outdoor distribution network, it's equally important that any new fiber can be easily connected with standard G.652 fiber, i.e. standard single mode fibers. The traditional problem for installers of optical fiber in buildings is that standard single-mode fiber cables suffer large optical losses if installed like copper cable.
Optical fiber containing airlines (also called voids or holes), non-periodic or continuous, herein called “microstructured fiber”, are being designed and produced for a number of applications. These microstructured fibers have low bend losses and the fiber optic cable containing such fibers can be installed like copper cable, without suffering large optical losses.
When a microstructured fiber is used in a system that requires the fiber to be mechanically spliced to a standard or another microstructured fiber, they first require polishing of the fiber end-face to assure a low loss connection and reliable contact between the fibers being connected (e.g., the fiber can not protrude from the connector ferrule end). However, polishing residue generated in the polishing process and the abrasive agent used in the polishing process may enter the void portion of the void-containing fiber to cause an increase in connection loss and a reduction in reliability.
It would therefore be desirable to develop additional bend tolerant fiber designs, particularly macrobend insensitive fibers which have minimal or no susceptibility to egress of polishing residue into the voids.